Systematic screening of the depigmenting of known and suspected chemicals to which man is expected environmentally will be performed. Studies will be done only on laboratory animals. The black guinea pig will serve as the model to observes the effects of chemicals on pigmented skin and hair. The goal is to identify substances which can and may produce leukoderma in man. Recommendations could then be supplied to those in industry and government who would be specifically concerned with safety and prevention of chemically induced "vitiligo."